Speaker Cooling

1. A playback device, comprising: at least one processor; at least one speaker; and memory having stored thereon instructions executable by the at least one processor to cause the playback device to perform functions comprising: while playing audible audio content via the at least one speaker, receiving input data indicating an instruction to stop playback of the audible audio content; determining that playback of the audible audio content has stopped; and based on the determination that playback of the audible audio content has stopped, playing inaudible audio content to cause the at least one speaker to vibrate thereby inducing air movement within the playback device.

2. The playback device of claim 1 , wherein the audible audio content is a first audible audio content, and wherein the functions further comprise: while playing the inaudible audio content, receiving input data indicating an instruction to begin playing a second audible audio content; and based on the input data indicating the instruction to begin playing the second audible audio content, (i) stopping playback of the inaudible audio content and (ii) beginning playback of the second audible audio content.

3. The playback device or claim 1 , wherein the functions further comprise: while playing the inaudible audio content, detecting, via a thermal sensor of the playback device, a temperature of the playback device; determining that the temperature is less than a threshold temperature; and stopping playback of the inaudible audio content after determining that the temperature is less than the threshold temperature.

4. The playback device of claim 1 , wherein playing the inaudible audio content comprises: playing the inaudible audio content for a pre-determined duration of time.

5. The playback device of claim 1 , wherein the functions further comprise: detecting, via a thermal sensor of the playback device, a temperature of the playback device; and wherein playing the inaudible audio content comprises playing the inaudible audio content while the detected temperature is greater than a threshold temperature.

6. The playback device of claim 1 , wherein the at least one speaker comprises one or more first speakers and one or more second speakers, and wherein playing the inaudible audio content comprises: causing the one or more first speakers to vibrate; and causing the one or more second speakers to vibrate out of phase with the one or more first speakers.

7. The playback device of claim 1 , wherein the inaudible audio content comprises audio content at frequencies above 20 KHz.

8. The playback device of claim 1 , wherein the inaudible audio content comprises audio content at frequencies below 20 Hz.

9. A non-transitory computer-readable medium having stored thereon instructions executable by a playback device to perform functions comprising: while playing audible audio content via at least one speaker, receiving input data indicating an instruction to stop playback of the audible audio content by the playback device; determining that playback of the audible audio content has stopped; and based on the determination that playback of the audible audio content has stopped, playing inaudible audio content to cause the at least one speaker to vibrate thereby inducing air movement within the playback device.

10. The non-transitory computer-readable medium of claim 9 , wherein the audible audio content is a first audible audio content, and wherein the functions further comprise: while playing the inaudible audio content, receiving input data indicating an instruction to begin playing a second audible audio content; and based on the input data indicating the instruction to begin playing the second audible audio content, (i) stopping playback of the inaudible audio content and (ii) beginning playback of the second audible audio content.

11. The non-transitory computer-readable medium of claim 9 , wherein the functions further comprise: while playing the inaudible audio content, detecting, via a thermal sensor of the playback device, a temperature of the playback device; determining that the temperature is less than a threshold temperature; and stopping playback of the inaudible audio content after determining that the temperature is less than the threshold temperature.

12. The non-transitory computer-readable medium of claim 9 , wherein playing the inaudible audio content comprises: playing the inaudible audio content for a pre-determined duration of time.

13. The non-transitory computer-readable medium of claim 9 , wherein the functions further comprise: detecting, via a thermal sensor of the playback device, a temperature of the playback device; and wherein playing the inaudible audio content comprises playing the inaudible audio content while the detected temperature is greater than a threshold temperature.

14. The non-transitory computer-readable medium of claim 9 , wherein the at least one speaker of the playback device comprises one or more first speakers and one or more second speakers, and wherein playing the inaudible audio content comprises: causing the one or more first speakers to vibrate; and causing the one or more second speakers to vibrate out of phase with the one or more first speakers.

15. A method comprising: while a playback device is playing audible audio content via at least one speaker, receiving, via the playback device, input data indicating an instruction to stop playback of the audible audio content by the playback device; determining, via the playback device, that playback of the audible audio content has stopped; and based on the determination that playback of the audible audio content has stopped, playing, via the at least one speaker of the playback device, inaudible audio content to cause the at least one speaker to vibrate thereby inducing air movement within the playback device.

16. The method of claim 15 , wherein the audible audio content is a first audible audio content, and wherein the method further comprises: while the playback device is playing the inaudible audio content, receiving, via the playback device, input data indicating an instruction to begin playing a second audible audio content; and based on the input data indicating an instruction to begin playing the second audible audio content, (i) stopping playback of the inaudible audio content and (ii) beginning, via the playback device, playback of the second audible audio content.

17. The method of claim 15 , further comprising: while the playback device is playing the inaudible audio content, detecting, via a thermal sensor of the playback device, a temperature of the playback device; determining, via the playback device, that the temperature is less than a threshold temperature; and stopping playback of the inaudible audio content after determining that the temperature is less than the threshold temperature.

18. The method of claim 15 , wherein playing the inaudible audio content comprises: playing, via the playback device, the inaudible audio content for a pre-determined duration of time.

19. The method of claim 15 , further comprising: detecting, via a thermal sensor of the playback device, a temperature of the playback device; and wherein playing the inaudible audio content comprises playing the inaudible audio content while the detected temperature is greater than a threshold temperature.

20. The method of claim 15 , wherein the at least one speaker of the playback device comprises one or more first speakers and one or more second speakers, and wherein playing the inaudible audio content comprises: causing, via the playback device, the one or more first speakers to vibrate; and causing, via the playback device, the one or more second speakers to vibrate out of phase with the one or more first speakers.